Driving device, exposure apparatus using the same, and device manufacturing method

Abstract

A driving device includes an electromagnetic actuator indicating a first coil and a second coil which detects a change in magnetic flux generated by the first coil, and an electromagnetic actuator controller which feedback-controls the electromagnetic actuator. The electromagnetic actuator controller includes a modulator which gives a modulated signal, which is generated based on a target value in the feedback control, to the first coil, and a demodulator which demodulates an output signal from the second coil, and in which the target value is a target thrust of the electromagnetic actuator. The electromagnetic actuator controller includes a scale converter which performs a square-root arithmetic operation for the target value to feedback-control the electromagnetic actuator based on an output signal from the scale converter and a signal demodulated by the demodulator.

1. A driving device comprising:
 (a) an electromagnetic actuator including a first coil and a second coil which detects a change in magnetic flux generated by said first coil; and 
 (b) an electromagnetic actuator controller which feedback-controls said electromagnetic actuator, wherein said electromagnetic actuator controller comprises:
 (i) a modulator which gives a modulated signal, which is generated based on a target value in the feedback control, to said first coil, wherein the target value is a target thrust of said electromagnetic actuator; and 
 (ii) a demodulator which demodulates an output signal from said second coil, and 
 
 said electromagnetic actuator controller includes a scale converter which performs a square-root arithmetic operation for the target value to feedback-control said electromagnetic actuator, based on an output signal from said scale converter and a signal demodulated by said demodulator. 
 
   
   
     2. The device according to  claim 1 , wherein said electromagnetic actuator controller feedback-controls said electromagnetic actuator based on the target value and the signal demodulated by said demodulator. 
   
   
     3. The device according to  claim 1 , wherein said electromagnetic actuator controller includes a phase adjustment unit in at least one of said modulator and said demodulator. 
   
   
     4. The device according to  claim 1 , wherein said electromagnetic actuator controller includes a filter which removes a harmonic component of the signal demodulated by said demodulator. 
   
   
     5. The device according to  claim 1 , further comprising:
 a power amplifier which drives said first coil; 
 a current detector which detects a current which flows through said first coil; and 
 a coil controller which feedback-controls the current which flows through said first coil. 
 
   
   
     6. The device according to  claim 1 , wherein said electromagnetic actuator includes an E core and an I core, and both of said first coil and said second coil are attached to said E core. 
   
   
     7. A stage device comprising:
 (1) a coarse moving stage; and 
 (2) a fine moving stage, wherein the fine moving stage is driven relative to the coarse moving stage by a driving device, wherein said driving device comprises:
 (a) an electromagnetic actuator including a first coil and a second coil which detects a change in magnetic flux generated by said first coil, and 
 (b) an electromagnetic actuator controller which feedback-controls said electromagnetic actuator, 
 wherein said electromagnetic actuator controller comprises:
 (i) a modulator which gives a modulated signal to said first coil; and 
 (ii) a demodulator which demodulates an output signal from said second coil. 
 
 
 
   
   
     8. An exposure apparatus comprising:
 (1) a driving device; 
 (2) an optical system to project exposure light applied to a master on which a pattern is formed onto a substrate; and 
 (3) a stage device which holds the substrate or the master and is aligned by said driving device, 
 wherein said driving device comprises:
 (a) an electromagnetic actuator including a first coil and a second coil which detects a change in magnetic flux generated by said first coil; and 
 (b) an electromagnetic actuator controller which feedback-controls said electromagnetic actuator, wherein said electromagnetic actuator controller comprises:
 (i) a modulator which provides a modulated signal to said first coil; and 
 (ii) a demodulator which demodulates an output signal from said second coil.